I thought about starting a new topic, but thought the input keeps with the continuity of this original topic.
I recently compared the SHT85 with the SHT75 in my Davis VP2 as well as a Davis mounted SHT31. I was able to get the data from the SHT85 with an old USB test kit I had from Sensirion and their RS485 Sensor Viewer 2.91 software. The siting of the SHT85 was not desirable due to cable length restrictions, but the sensor comes with its own sensor-mounted filter and I placed it in the Davis 7714 radiation shield. If temperatures between the sensors were the same, I was able to compare humidity values directly. In times when they weren't, I used dewpoint.
Initially, the SHT85 data seemed promising, running 6-8 percentage points lower in humidity than the SHT75 (2-3°F lower in dewpoint). Even after a period of high humidity, where both sensors reached 98%, the SHT85 would read a lower humidity when the air dried out again. Unfortunately, after a longer period of high humidity, the high humidity bias presented itself in the SHT85 and pretty much matched the SHT75 exactly. After the test, I brought the high bias SHT85 and SHT75 inside to compare with the Davis-mounted SHT31 which I have baked previously and has been inside in low humidity. Both the SHT75 and SHT85 perform about the same or a little better even with the high humidity bias present.